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Your question is better expressed as why can an ac circuit be shorted to earth when a dc circuit can't be? With an ac supply only the positive feed is actually present at the socket. There is no negative, just a neutral return which is actually connected to earth at the power station / substation. Earthing an ac curcuit just provides a shorter route to the earth, which is where it would have gone anyway. The earth connection at the socket is just to provide a safe means of dumping the current locally in the event of a fault. In a dc circuit the current has nowhere to go, other than to the negative terminal / rail. Without both positive and negative being present no circuit can be formed.
Wiki User
∙ 16y ago
Wiki User
∙ 13y agoA transformer reacts to the rate of change of its applied voltage. The primary will create an magnetic field with DC but the secondary will not produce any e.m.f if there is no change in magnetic field. Therefore there will be no secondary voltage delivered.
Be warned, that connecting and disconnecting DC to a transformer may result in very high voltages for that instant in both secondary and primary sides. The reason is, that there is magnetic energy stored because of the DC and there is a rate of change involved on that instant where the contact is closed or opened.
Wiki User
∙ 12y agoTransformers use fluctuating magnetic fields in order to work. But for a dc circuit, electro magnetic field throughout a circuit is constant. So, we can not use a transformer on a dc circuit.
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What is the basic function of chopper circuit?
to convert the DC into DC.............
If you have a DC passing through a circuit will the current decrease when you add a DC motor and if so by how much?
In the circuit where the DC motor is added, it was not specified whether the motor was added in series or in parallel to circuit elements. If it was added in series, it will increase circuit resistance and it will cause circuit current to go down. In parallel, the motor will reduce total circuit resistance, and circuit current will increase.
In the simplest of dc circuits where the resistance is zero what kind of circuit is it?
A short circuit.
How does current flow in a standard DC circuit?
(the current in the earth direction is going left of use) 8th grade studend juicey babee
Why transformer action can take place in DC circuit?
Not clear what your question is. First of all, circuits are not classified as DC and AC. Circuits are what they are, and you can apply either AC or DC to any circuit. However, considering a circuit that was designed only for use with DC applied. Still your question is unclear. What is transformer action? "Transformer Action" happens in a transformer.
Which circuit element is used to block DC in an electronic circuit?
Capacitance will block DC
Why DC supply is used in control circuit?
dc supply is used for control circuit because dc current is an independent source .
Why use DC circuit when frequecy is zero?
DC has no frequency.
What is the basic function of chopper circuit?
to convert the DC into DC.............
Can you call dc-dc converters as a chopper circuit?
yes definitely you can
If AC is replaced by DC in a fluorescent lamp circuit will the circuit work?
No.
If Transformer on a DC circuit?
Trsansformers work on mutual induction principle caused by the changing magnetic field. Since there is no changing magnetic field i.e there is no "+" and "-" cycle in DC source supply so transformer cant work on a DC source. Its core will become permanent magnet.
Can a step down transformer increase current in a DC circuit?
Transformers only work with alternating currents. So the answer is Yes, BUT it would have to be a DC Pulsing circuit. using flip flop circuit or a 555 circuit or chop circuit.
If you have a DC passing through a circuit will the current decrease when you add a DC motor and if so by how much?
In the circuit where the DC motor is added, it was not specified whether the motor was added in series or in parallel to circuit elements. If it was added in series, it will increase circuit resistance and it will cause circuit current to go down. In parallel, the motor will reduce total circuit resistance, and circuit current will increase.
Why capacitance is not used in DC circuits?
as it acts ideally as open circuit for dc
Why current is supplied to DC motor?
What supplies a dc motor is not current, but voltage. Current is what flows in the circuit formed by the dc motor and for the charge. That current varies according to the resistance of the circuit.
How are the capacitors treated in the dc equivalent circuit of an amplifier?
In dc equivalent circuit of an amplifier all capacitors are replaced by open circuit because capacitor block dc. As , Xc=1/2πfC We know that that frequency of dc is zero so Xc will infinite so we replace all capacitors with open circuit.
